 |
 |
 |
||
|
|
||||
 |
|
|
| Introduction and Specifications | ||||
 ;) The Xonar Essence STX audio card boasts a host of features that are clearly aimed at end users wanting the best possible listening experience their PC can offer. In this HotHardware evaluation, we are going to explore this card's features and performance with particular emphasis paid to sound quality.
The Xonar Essence STX comes nicely packaged in a display box with "124 dB SNR / Headphone Amp Card for Audiophiles" proclaimed on the front and containing one each of the following:
|
| Xonar Essence STX | ||||||
;) One thing that is immediately apparent about the Xonar Essence STX is the absence of the 1/8" jacks normally used on most cards for I/O. Instead this card features gold-plated RCA connectors for left and right line out. Gold lined 6.3MM TRS (Tip-Ring Sleeve) Headphone out and microphone/line in jacks are accompanied by a gold-plated optical RCA output jack. The analog output section of the card is encased in shielding to further isolate the signals. The components mounted to the PCB are truly what define the audiophile classification of this card. Featuring Nichicon "Fine Gold" professional audio capacitors for warm bass and clear highs, a Burr-Brown PCM 1792A Digital-to-Analog converter rated at 127dB signal-to-noise ratio and the unique addition of swappable OPAMP sockets to customize the sound to your personal preference. In addition a built-in TI TPA6120A2 headphone amp provides the extra power to handle high-end "cans" with up to 600ohms of impedance and less than 0.001% distortion. The Xonar essence with its advertised 124dB Signal to Noise Ratio should yield an improvement many times over the sound quality of typical (HD) on-board sound solutions that usually yield a SNR in the 83-88dB range. The inclusion of low latency ASIO drivers gives you the added benefit of using the ASUS Xonar in audio applications such as soft-synths like Reason, Ableton Live, or Reaktor. Of course without MIDI ports you will need to use USB keyboards and controllers or add a MIDI card.
|
| ASUS XONAR Essence STX Driver Features | ||||
Lets take a quick tour of the Xonar Audio Center, its layout and controls. For a full explanation of each feature, we'd suggest you refer to our previous Xonar covers and specifically take a look here. ;)
;)
;)
Audio Center Main Mixer Playback The Xonar Audio Center in its compact mode allows access to all the basic controls such as volume, smart volume, mute and the different DSP modes. Click the up arrow and it expands to reveal the main mixer section which provides access to adjust the sample rate, analog out, SPDIF out and various Dolby settings. Click the Mixer button and you have access to the playback level controls. ;)
;)
;)
Mixer Record Effects KARAOKE Still under the mixer section you can click the record button and it provides access to all input level controls. The Effect button allows access to the EQ and various presets plus environmental settings. The KARAOKE button provides access to the various KARAOKE settings such as key shifting, vocal cancellation, and mic echo. ;)
;)
FlexBass Vocal Effects The FlexBass section is where you can activate and adjust the low frequency crossover point. Click the VocalFX button and you will see and be able to set the 3D game, VOIP, ChatEX, and Magic Voice settings. |
| Benchmarking Test System and Procedures | ||||||||||||||||||
|
| Rightmark Audio Analyzer 6.2.2 | ||||||||
Rightmark Audio Analyzer 6.2.2 works by generating and outputting tones that are measured by the input section of a sound card. The data is analyzed by the software and results are generated. First, we have the results from the onboard Realtek HD Audio 
Here are our results from the M-Audio Delta 1010LT 
Now we have the ASUS Xonar results from line out to line in 
Now we see the results of the headphone out to line in test 
Synopsis: The Asus Xonar Essence STX delivers exactly as promised in these benchmarks. With a measured dB of 116.7@192khz that is just under the max capable level of the input section (118dB). Also, taking into effect that the loopback cables used can slightly decrease performance due to interference that gets through the shielding, these results are very impressive to say the least. |
| Centrance ASIO Latency Test Utility v3.7 | |||||||||
 Audio Stream Input/Output (ASIO) is a computer sound card driver protocol that provides for low latency interaction between sound cards and professional audio applications. ASIO drivers also reduce the latency between external keyboards or controllers and sound applications. Using low latency ASIO drivers, when a key is depressed on the controller, there is no perceived delay time before the sound is generated by the soft synth or other sound applications. This is of course also dependent on the performance level of the sound card, computer and number of active instruments or tracks used. For reference, latency times of 2-4ms are practically undetectable by human hearing. The average hardware synthesizer has a latency of 2ms.
|
|||||||||
| Gaming performance | ||||
Even though the ASUS Xonar is marketed as an audiophile card we ran some time demos in a couple of games, just to look at it from a gaming performance angle as well. On Half Life 2 EP2 we ran a pre-recorded demo at high and low quality sound settings with the results below. Although the results in FPS do not show any gains the sound quality was much crisper, clearer, and responsive, with the ASUS Xonar. Please note, we substituted an ASUS Radeon 3870 for the Quadro card in the workstation for the gaming tests   Improved sound quality during game play was very noticeable. Effects were crisp, and in your face whether through the headphones or the monitors. We also noticed improved separation from background music and in game action sounds. The "game" DSP mode was used throughout the tests. |
| Audio Playback Performance - Headphones | ||||
A higher SNR allows for more gain without distortion, so you hear all of the subtle nuances complete with end taper or cut from notes that are usually edited in post production for better separation and crisp transitions. With the Xonar Essence STX, one of the first things you'll note as an audiphile, is that the "muddiness" is gone in high quality tracks. Listening to your music collection using this card through a high quality set of headphones makes for an addictive experience. You will want to go back and listen to all of your tracks that have been mastered or encoded to higher specs over and over. Listen to a 192 Kbit/s vs 320 Kbit/s track and you will notice the difference in seconds. The only let down comes when you listen to the same music through another means as this aural experience will be hard to duplicate beyond the cozy cups of your favorite headphones. The true surround features via the card's optical outoput require a Dolby decoder but as it says right on the box, this is an Audiophile Headphone card. Although we were using a low impedance (24 ohms) headset (Sony MDR V700DJ) we still needed to kick the headphone gain setting up to +12DB (High Gain for 64~300 ohms) for our bass heavy listening style. By the way, our high end reference AKG K702's headphones at 62 ohms worked on the same settings as well. As we are sure most of you know, bass frequencies have a contradicting effect on highs so balance is the key, but not very hard to achieve at 112+ SNR.  A nice feature of the XONAR EQ section is it actually uses values that can be perceived by humans - 30hz to 16khz. 30Hz can be felt slightly depending on your choice of headphones and 16khz can be heard depending on your age. The Xonar EQ also doesn't have that canned, slewed, sound you experience when adjusting the EQ in certain media players. It behaves as if you are turning the pots on an actual mixer console. TIP: Don't even try the stock presets of the card. Make your own user defined presets (UserDef) and save them. We tried the user defined presets on multiple types of media and it just confused our hearing temporarily while adjusting back to our preferred sound. Testing Selections: Creed - One - Direct from CD Very nice track and the Xonar made the bass and guitar very punchy. Queen - Under Pressure - Direct from Gold Remastered series CD The great sound of analog mastered music could be heard without sounding flat. Joop - The Future (Markus Schulz Remix - 320k/Bits MP3 Great trance track and the Xonar had the steady bass beat pounding in the cups. The Fast and the Furious: Tokyo Drift - Movie - DVD Tons of sounds and great music here that highlighted the Xonar's performance. Tiesto - Elements of Life World Tour - Live DJ Concert - DVD This in-concert trance DJ DVD peppered with live acts featured great vocals and intricate arpeggios great for testing the Xonar. |
| Audio Playback Performance - Speakers | ||||
Normally, when calibrating a sound system and speakers for a room, we would set the speakers up in their final positions and then put a mobile spectrum analyzer at the key listening point. We would then attach either a standard gain or boosted gain (for microphone inputs) pink noise generator to a line in and bring the levels up. The EQ would then be adjusted to 0dB all the way across the shown EQ spectrum on the mobile analyzer. This would give us perfectly flat response for the room, meaning it would account for the different surfaces, materials and room acoustics present. Correctly mastered tracks should not need additional equalizing except to adjust for the personal preferences of the listener and the environment.  Since we are doing subjective analysis based on what the typical end user could expect we are doing all this by ear. The speakers wer set up on the opposite side of the room from the listening position, 10 feet apart, at listening height (centered at ear level), and 10" forward from the wall. A brick wall provided the backdrop. The EQ has been adjusted as shown to the rightAlesis M1 Active MKII monitors were chosen as they do not have a prohibitive price but provide specs well within the range of the card tested. Alsesis M1 Active II specs (for reference)
All tracks were listened to at "normal" (full gain on the cabinets and 50% volume on the Xonar Controller/Mixer) levels initially. Electronica or "trance" music uses more of the perceivable spectrum than modern Top 40/Rock/Etc. The only equivalent would be classical music but in keeping with its true nature it is mastered to allow the subtle imperfections in very high priced handcrafted instruments known as "character" and reflected as "colour". With our choice of source music every arpeggio, staccato, and effect used was instantly perceived in the manner the producer meant. In other words the reference material was reproduced spot on. Even after pushing the levels to 80% which normally induces distortion on this set of monitors, the high SNR of (measured 116dB) prevailed with even better separation and frankly a little too much bass which was adjusted slightly lower. We even listened to some tracks that are not typically received as high fidelity, but feature those aforementioned subtle nuances that illicit emotions of a true audiophile as we were not so consumed with frequency response that we ignore simply great music. Testing Selections: Andrea Bocelli - Con te partirò in FLAC lossless audio Andrea's crescendo makes this track powerful and Xonar captured it. Blur - Song 2 - direct from CD Great track that was mastered in a grunge style and the sound carries over. The Xonar accurately produced the great "raunchy" feel of this track. Cold Play - Viva La Vida - 320k/Bits MP3 Great track that covers the spectrum of sound with orchestration and great vocals. Street Kings - Movie - DVD Loved the sound Keanu's Dodge Hemi growling in the speakers. Armin Only:Imagine - Live DJ Concert - DVD The Xonar definitely enhanced this beautifully mastered recorded performance. |
| Summary and Conclusion | ||
| The Asus Xonar Essence STX is marketed as an Audiophile's sound card. That being said, we could do without some of the non-essential bells and whistles. An audiophile will never be satisfied with the stock EQ presets and there are plenty. The rotating surround sound is more a novelty than anything else. The line out left and right slides on the mixer could use a link that allows them to be moved together so both do not have to be adjusted independently. The only need we see for this is that on some systems there is a higher output on the left channel which could be accommodated by circular gain controls at the top of the slides. We could do without the karaoke section as well. We understand most of these driver features are carried over from other Xonar sound cards but Asus is setting a new standard here that merits a refresh of feature controls, and perhaps a nice packaging of encoders and audio applications. Finally, one thing we noticed while testing is a clicking sound upon booting, shutting down and switching inputs on the card. Don't be alarmed, this is just the sound of an internal switch that resets the circuits to prevent bleed over from capacitor voltage. 
|
;)
;)
;)
;)
;){kind=link}